Quick Answer. A low hemoglobin count, also known as anemia, is caused by pregnancy, a menstrual period, a diet low in iron, blood loss, or a disease that causes the body to produce fewer red blood cells or to destroy red blood cells. According to the Mayo Clinic, medications also sometimes cause anemia.
A cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell, cytolytic T cell, CD8+ T-cell or killer T cell) is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.
Small lymphocytes 7â8 Large lymphocytes 12â15. 1  B cells: releases antibodies and assists activation of T cells. 2  T cells: CD4+ Th (T helper) cells: activate and regulate T and B cells. CD8+ cytotoxic T cells: virus-infected and tumor cells. 3  Natural killer cells: virus-infected and tumor cells.